Also:

Activists are people with agendas. They are not common in the general population, but they make a stunningly disproportionate amount of noise. Activists, in my experience, spend large chunks of time surfing the web for materials that run counter to their causes. Activists are very likely to leave comments — especially nasty or insulting comments — on blogs.

Commenting on blogs is an easy but not terribly effective way to promote an agenda. But it isn’t the only one out there. Every once in a while an activist puts in some real effort and does something that makes a big splash.

That was what happened in 1998 when an anti-vaccine activist, posing as a scientist, managed to publish a report in the completely reputable British medical journal, Lancet.

The activist was the lead author on a study that linked childhood vaccines to autism. As a result, many parents declined to vaccinate their children. NPR recently reported that four children are estimated to have died as a result. That is not a huge number, but it isn’t zero. And zero is the number of autism cases that were prevented by decreased vaccination.

The paper was steadily discredited during the decade after its publication. 10 of the paper’s 13 authors renounced it. Lancet retracted it. And most recently, an evaluation of the activist’s “scientific” techniques determined that they weren’t scientific at all. The paper was a fraud, designed to promote an agenda.

What have been the results of the fraud? Not one case of autism has been prevented. An estimated four children are dead. Confusion about both vaccines and autism is more widespread. And, critically, legitimate debate over vaccinations — in both human and veterinary medicine — has been hurt.

I want to go on the record about this: there is room for legitimate debate over vaccinations in animals. There is no question that vaccinations prevent deadly disease. But over-vaccination may — I said may — be linked to autoimmune disease. In cats, some vaccines most certainly are linked to cancers.

Our pets deserve an honest debate about vaccines. They deserve honest, legitimate scientific research about the matter.

Anti-vaccine activists exist in the animal world. Sadly, for activists (like politicians), the truth sometimes can interfere with their agenda. They (again, like politicians) sometimes work to stifle the truth, and to block honest inquiry and debate.